tests/mir-opt/match_branch_simplification_aliasing.union_fields.MatchBranchSimplification.diff

- // MIR for `union_fields` before MatchBranchSimplification
+ // MIR for `union_fields` after MatchBranchSimplification
  
  fn union_fields(_1: Foo) -> Foo {
      let mut _0: Foo;
      let mut _2: U;
      let mut _3: u8;
  
      bb0: {
          (_2.1: Foo) = copy _1;
          _3 = discriminant((_2.1: Foo));
          switchInt(copy _3) -> [0: bb2, 1: bb3, otherwise: bb1];
      }
  
      bb1: {
          unreachable;
      }
  
      bb2: {
          (_2.0: Foo) = Foo::A;
          goto -> bb4;
      }
  
      bb3: {
          (_2.0: Foo) = Foo::B;
          goto -> bb4;
      }
  
      bb4: {
          _0 = copy (_2.0: Foo);
          return;
      }
  }